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where to get good flux

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where to get good flux | 2 April, 2013

So where does one get good flux? the engineers had a little bottle of good flux that the owner of the company liked, it had a oily feel to it. So then the company purchased some more since the engineers look like it was about to run out, the owner of the company was not impressed, it had a watery feel to it. It could of been urine but I dont think so.

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where to get good flux | 2 April, 2013

Too many hands in the bucket, unless the owner is one of the engineers. Typically flux is not rated or classified by "feel".

What are you soldering? Wires? Components to PCB?

What is your cleaning capability or requirement? Aqueous? No-Clean? Ultrasonic or Vapor?

You made the question tough by the lack of information.

Any solder distributor will sell you a flux of some kind, but you'll have to qualify it better than "oily" or "watery", or even "urine-like".

Good Luck!

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where to get good flux | 3 April, 2013

Yes well, now we used to add a bit of flux to our leaded paste to make it slightly runny, But when we went to unleaded paste the joker who came in from another company to set the temperature on the oven said "you dont add anything to unleaded paste!......" ".....besides unleaded paste uses resin not flux" (what ever difference that is)

Now sometimes the inductors go through the oven and they stand up on the end, after I lay them flat with hot air, there is (dry joint) now I used to add a bit of paste, but even a smallest amount of paste will sometimes make the joint look like a ugly over dose of too much solder, now I found by putting a small amount of flux in the joint and then heating with hot air it will make a beautiful soldering joint almost as good as the oven does (and a lot better than adding the smallest amount of solder)

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where to get good flux | 3 April, 2013

In agreement, in that you should have already printed enough paste on the board to accomodate the joint. Adding paste would give the result you described. (too much solder) Adding a little flux (only) and heat would be the correct path out of that situation.

Of course there is something to be said about fixing what might be wrong in the original process that is causing the tombstone defect (standing on end). Thermal Balance, PWB Wetting, Component Solderability, etc...

Your comments about adding flux to your paste bother me just a little, since the paste should be at the right consistency already, and you shouldn't be adding flux to either regular or lead free solder in a typical process.

Flux is your friend. Be sure you are capable of a good cleaning of the flux residue afterwards, though!


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where to get good flux | 6 April, 2013

this is on a repair when I add more paste, I am sorry I asked

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